Gestational Diabetes

What causes gestational diabetes?

Healthcare providers do not know what causes gestational diabetes. 

What happens with gestational diabetes?

The placenta gives your growing baby nutrients and water. The placenta also makes several hormones to keep the pregnancy healthy, including: 

• Estrogen
• Progesterone
• Cortisol
• Human placental lactogen

These hormones can affect how your body uses insulin. During pregnancy, more fat is stored in your body, you take in more calories and you may get less exercise. All of these things can make your blood sugar levels higher than normal and possibly lead to gestational diabetes.

As the placenta grows, it makes more of the hormones. The risk for insulin resistance becomes greater. Normally your pancreas is able to make more insulin to overcome insulin resistance. But if it cannot make enough to overcome the effects of the placenta’s hormones, you can develop gestational diabetes.

Who is at risk for gestational diabetes?

Any woman can develop gestational diabetes during pregnancy. But you may be more likely to get it if you:

• Are overweight or obese
• Have a family history of diabetes
• Have given birth to a baby weighing more than 9 pounds
• Are older than 25
• Are African American, American Indian, Asian American, Hispanic or Latino or Pacific Islander
• Have prediabetes (impaired glucose tolerance)
• Have hypertension

What are the symptoms of gestational diabetes?

Gestational diabetes typically does not cause any symptoms. That’s why it’s important to get tested for it if you are at high risk. However, if your blood sugar levels are very high, you may have these symptoms:

• Urinating more than normal
• More hungry or thirsty than normal  
• Blurred vision
• Nausea and vomiting
• Weight loss even though you are hungrier

How is gestational diabetes diagnosed?

You should be tested for gestational diabetes between weeks 24-28 of pregnancy. The American Diabetes Association also recommends that you be tested for type 2 diabetes if you have risk factors for this condition. This testing should be done at your first prenatal visit.

Screening is done by these tests:

• One-hour glucose tolerance test. You drink a special beverage high in sugar. One hour later, the healthcare provider measures your blood sugar/glucose levels. If your levels are higher than a certain level, this is considered an abnormal result.
• Three-hour glucose tolerance test. If the 1-hour test is abnormal, you will have a second glucose tolerance test done to confirm the diagnosis. You will drink another special beverage. Your healthcare provider will measure your blood sugar levels 1 hour, 2 hours and 3 hours later. You have gestational diabetes if at least two of the glucose measurements are higher than normal.

If you are diagnosed with gestational diabetes, you should get tested for diabetes 6 to 12 weeks after your baby is born. You should also get this screening at least every three years for the rest of your life.

What is the treatment for gestational diabetes?

Your healthcare provider will determine the best treatment for you based on your:

• Age
• Overall health and past health
• Level of sickness
• Ability to handle specific medicines, procedures or therapies
• Opinion or preference

Treatment for gestational diabetes focuses on keeping your blood sugar levels in the normal range. Treatment may include:

• Special diet. Ideal diet should include five servings of vegetables, fruit, low-fat or nonfat dairy products and lean meats daily; using liquid fats instead of solid fats for cooking; eating whole grains; and avoiding high-calorie snacks and sweets.
• Exercise. You should do moderate exercise unless otherwise directed by your healthcare provider.
• Daily blood glucose monitoring. Your goal is to keep your blood sugar levels lower than 130-140 mg/dL one hour after eating.
• Insulin injections. You may need insulin injections or other oral medications to control blood sugar levels. 

What are the complications of gestational diabetes?

Gestational diabetes usually does not cause birth defects, but it can affect your baby in other ways if your blood sugar levels are not under control. Two major health problems that can develop from gestational diabetes are macrosomia and hypoglycemia.